This research describes the application of portable field Raman spectroscopy combined with a statistical analysis of the resulting spectra, employing principal component analysis (PCA) and linear discriminant analysis (LDA), in which we determine that this method provides a high degree of reliability in the early detection of Huanglongbing (HLB) on Sweet Orange, disease caused by the bacteria Candidatus Liberibacter asiaticus. Symptomatic and asymptomatic plant samples of Sweet Orange ( Citrus sinensis), Persian Lime ( C. latifolia), and Mexican Lime ( C. aurantifolia) trees were collected from several municipalities, three at Colima State and three at Jalisco State (HLB presence). In addition, Sweet Orange samples were taken from two other Mexican municipalities, one at San Luis Potosí and the other at Veracruz (HLB absent). All samples were analyzed by real-time PCR to determine its phytosanitary condition, and its spectral signatures were obtained with an ID-Raman mini. Spectral anomalies in orange trees HLB-positive, were identified in bands related to carbohydrates (905 cm ⁻¹ , 1043 cm ⁻¹ , 1127 cm ⁻¹ , 1208 cm ⁻¹ , 1370 cm ⁻¹ , 1272 cm ⁻¹ , 1340 cm ⁻¹ , and 1260–1280 cm ⁻¹ ), amino acids, proteins (815 cm ⁻¹ , 830 cm ⁻¹ , 852 cm ⁻¹ , 918 cm ⁻¹ , 926 cm ⁻¹ , 970 cm ⁻¹ , 1002 cm ⁻¹ , 1053 cm ⁻¹ , and 1446 cm ⁻¹ ), and lipids (1734 cm ⁻¹ , 1736 cm ⁻¹ , 1738 cm ⁻¹ , 1745 cm ⁻¹ , and 1746 cm ⁻¹ ). Moreover, PCA–LDA showed a sensitivity of 86.9 % (percentage of positives, which are correctly identified), a specificity of 91.4 % (percentage of negatives, which are correctly identified), and a precision of 89.2 % (the proportion of all tests that are correct) in discriminating between orange plants HLB-positive and healthy plants. The Raman spectroscopy technique permitted rapid diagnoses, was low-cost, simple, and practical to administer, and produced immediate results. These are essential features for phytosanitary epidemiological surveillance activities that may conduct a targeted selection of highly suspicious trees to undergo molecular DNA analysis.

In growing Mexican cities, there are few studies on air pollution, especially on the topic of characterization for the chemical composition of Particulate Matter (PM). This work presents an X-ray Fluorescence (XRF) analysis and Total Carbon analysis of PM_2.5 in a two-year monitoring campaign from 20 May 2017 to 30 July 2018, collecting 96 daily samples in the northeast area of San Luis Potosi city to reconstruct the gravimetric mass and perform a source apportionment study using the Positive Matrix Factorization model (PMF). Concentration differences were due to different yearly seasons. In the year 2017, there was a major influence on heavy metals (V, Cr, Mn, Ni, Cu, Zn, Pb), and for the year 2018, there was a major crustal elements concentration (Na, Al, Si, P). Heavy metal concentrations are higher than any worldwide regulation limit. After applying these methods to the 49 samples collected for the year 2017, the mass reconstruction was nearly 70% of the gravimetric mass. XRF analysis quantified 17 elements (Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn) in addition to Total Carbon (Organic Carbon (OC) + Elemental Carbon (EC)). PMF receptor model was applied to identify possible contribution sources and resolved seven physically interpretable factors that contributed to the ambient particulate pollution at the sampling site: Urban Dust (24.2%), Mobile Sources (22.2%), Chemical industry (18.2%), Oil combustion (16.3%), Smelting Industry (12.4%), Fuel Oil + Ceramic Industry (4.4%), and Braking (2.3%). However, the brick kiln’s emissions may be present in at least four of the emission sources due to several types of combustible employed.

The Mexican sugar industry has a long history. It is an industry which combines the agricultural activities of growing, harvesting and transporting sugarcane with the industrial factory production of raw and refined sugar and many specialty and downstream products. To compete in a global economy, it is important to establish performance criteria/benchmarks for the purpose of achieving lowestcost sugar production in terms of technical competitiveness, productivity and efficiency according to three aspects (sucrose yields, sugarcane per hectare and factory). This article discusses some economic and technical competitiveness indicators for the performance assessment of the Mexican sugarcane industry, using various tools (benchmarking and Porter's diamond methodologies) for analyzing performance parameters. The results suggest that there are numerous technical and economic factors that limit growth, since the Mexican industry has remained highly non-competitive and needs to improve and innovate in reducing costs, particularly regarding sugarcane farming business performance (raw material, harvest and transport costs), and the development of planning strategies to improve profitability. The other major area identified is sugar process diversification based on by-products (waste, chaff, molasses, filter mud and stillage). This is highly relevant to the sugar industry as a source of renewable energy and raw materials.

La caña de azúcar es una de las más importante actividades productivas en la región Huasteca de México y que requiere de planes para incrementar la productividad y disminuir la incertidumbre ante las limitaciones y el mercado. Mediante la zonificación productiva potencial del cultivo a través de una evaluación multicriterio AHP (proceso de jerarquías analíticas) en un ambiente SIG (Imgenes Lansat 7 ETM+), se generaron mapas temáticos (climáticos y edafológicos) relacionados con las variables del cultivo de caña empleando ILWIS y ESRI ArcGis 9.2. La metodología AHP proporcionó el marco de evaluación y la zonificación del cultivo al sintetizar la interacción entre las variables que determinan la productividad del cultivo y representan el punto clave del manejo agronómico espacial en Huasteca. Los resultados demostraron que la metodología de percepción remota, AHP y SIG, pueden servir además como herramienta efectiva, de bajo costo.

En el presente artículo se analizan y se presentan las circunstancias físicas, sociales y económicas que en conjunto afectan al panorama y a la problemática actual del abastecimiento de agua potable de la zona metropolitana de la ciudad de San Luis Potosí. Entre los temas que se abordan se encuentra la relación entre la disponibilidad del agua y el incremento de la población, así como la evolución de la extracción de aguas subterráneas. Por otra parte, la investigación muestra un diagnóstico de la situación en que se encuentra actualmente el abasto de agua potable en la ciudad de San Luis Potosí y en las áreas aledañas; también plantea el probable escenario del futuro inmediato.

La sanidad y la protección vegetal tienen como finalidad generar acciones para el control de plagas y enfermedades agrícolas, el uso de plaguicidas y la determinación de estatus fitosanitario para la comercialización en el marco de la seguridad alimentaria. Sin embargo, la protección vegetal como instrumento normativo y de regulación se ha quedado en la escala mundial y nacional, cuando el manejo de plagas es principalmente local (la finca o la parcela). Existe una desarticulación institucional y territorial en cuanto a la regulación de plaguicidas. A nivel mundial, se reconoció el Manejo Integrado de Plagas (MIP) cómo la política pública del manejo y control de plagas, a nivel local esa estructura no llegó y no se aplica por la inexistencia del modelo de extensionismo fitosanitario. Los actores que controlan la gestión de plaguicidas son las llamadas “casas agronómicas” que son pequeños negocios particulares que enfrentan políticas laxas tanto agrícolas, ambientales y de salud, actúan al margen de la normativa estatal y nacional. Establecen acuerdos y “reglas de juego” que estimulan y facilitan el uso indiscriminado de los agroquímicos. Tal es caso del valle agrícola de Rioverde y Ciudad Fernández, San Luis Potosí, particularmente en el ejido El Refugio se aplican plaguicidas restringidos como: Diazinon, Glifosato, Carbofuran, Clorpirifos Etil, Metamidofos, Metomilo y Monocrotofos, todos Plaguicidas Altamente Peligrosos (PAP). Por lo antes mencionado, este trabajo tuvo como objetivo, demostrar que los problemas de gobernanza territorial constituyen el reto más importante para afrontar y resolver el problema de plaguicidas en México.